import tensorflow as tf

input1 = tf.placeholder(tf.float32)
input2 = tf.placeholder(tf.float32)
output = tf.multiply(input1, input2)
with tf.Session() as sess:
    res = sess.run([output], feed_dict={input1:[7.], input2:[2.]})
    print(res)
# 输出:
# [array([ 14.], dtype=float32)]